On Wed, Feb 26, 2025 at 05:40:02PM +0530, Aneesh Kumar K.V wrote: > Xu Yilun <yilun.xu@xxxxxxxxxxxxxxx> writes: > > > On Fri, Feb 21, 2025 at 01:43:28PM +0530, Aneesh Kumar K.V wrote: > >> Alexey Kardashevskiy <aik@xxxxxxx> writes: > >> > >> .... > >> > >> > > >> > I am trying to wrap my head around your tsm. here is what I got in my tree: > >> > https://github.com/aik/linux/blob/tsm/include/linux/tsm.h > >> > > >> > Shortly: > >> > > >> > drivers/virt/coco/tsm.ko does sysfs (including "connect" and "bind" to > >> > control and "certs"/"report" to attest) and implements tsm_dev/tsm_tdi, > >> > it does not know pci_dev; > >> > > >> > drivers/pci/tsm-pci.ko creates/destroys tsm_dev/tsm_dev using tsm.ko; > >> > > >> > drivers/crypto/ccp/ccp.ko (the PSP guy) registers: > >> > - tsm_subsys in tsm.ko (which does "connect" and "bind" and > >> > - tsm_bus_subsys in tsm-pci.ko (which does "spdm_forward") > >> > ccp.ko knows about pci_dev and whatever else comes in the future, and > >> > ccp.ko's "connect" implementation calls the IDE library (I am adopting > >> > yours now, with some tweaks). > >> > > >> > tsm-dev and tsm-tdi embed struct dev each and are added as children to > >> > PCI devices: no hide/show attrs, no additional TSM pointer in struct > >> > device or pci_dev, looks like: > >> > > >> > aik@sc ~> ls /sys/bus/pci/devices/0000:e1:04.0/tsm-tdi/tdi:0000:e1:04.0/ > >> > device power subsystem tsm_report tsm_report_user tsm_tdi_bind > >> > tsm_tdi_status tsm_tdi_status_user uevent > >> > > >> > aik@sc ~> ls /sys/bus/pci/devices/0000:e1:04.0/tsm_dev/ > >> > device power subsystem tsm_certs tsm_cert_slot tsm_certs_user > >> > tsm_dev_connect tsm_dev_status tsm_meas tsm_meas_user uevent > >> > > >> > aik@sc ~> ls /sys/class/tsm/tsm0/ > >> > device power stream0:0000:e1:00.0 subsystem uevent > >> > > >> > aik@sc ~> ls /sys/class/tsm-dev/ > >> > tdev:0000:c0:01.1 tdev:0000:e0:01.1 tdev:0000:e1:00.0 > >> > > >> > aik@sc ~> ls /sys/class/tsm-tdi/ > >> > tdi:0000:c0:01.1 tdi:0000:e0:01.1 tdi:0000:e1:00.0 tdi:0000:e1:04.0 > >> > tdi:0000:e1:04.1 tdi:0000:e1:04.2 tdi:0000:e1:04.3 > >> > > >> > > >> > SPDM forwarding seems a bus-agnostic concept, "connect" is a PCI thing > >> > but pci_dev is only needed for DOE/IDE. > >> > > >> > Or is separating struct pci_dev from struct device not worth it and most > >> > of it should go to tsm-pci.ko? Then what is left for tsm.ko? Thanks, > >> > > >> > >> For the Arm CCA DA, I have structured the flow as follows. I am > >> currently refining my changes to prepare them for posting. I am using > >> tsm-core in both the host and guest. There is no bind interface at the > >> sysfs level; instead, it is managed via the KVM ioctl > >> > >> Host: > >> step 1. > >> echo ${DEVICE} > /sys/bus/pci/devices/${DEVICE}/driver/unbind > >> echo vfio-pci > /sys/bus/pci/devices/${DEVICE}/driver_override > >> echo ${DEVICE} > /sys/bus/pci/drivers_probe > >> > >> step 2. > >> echo 1 > /sys/bus/pci/devices/$DEVICE/tsm/connect > >> > >> step 3. > >> using VMM to make the new KVM_SET_DEVICE_ATTR ioctl > >> > >> + dev_num = vfio_devices[i].dev_hdr.dev_num; > >> + /* kvmtool only do 0 domain, 0 bus and 0 function devices. */ > >> + guest_bdf = (0ULL << 32) | (0 << 16) | dev_num << 11 | (0 << 8); > >> + > >> + struct kvm_vfio_tsm_bind param = { > >> + .guest_rid = guest_bdf, > >> + .devfd = vfio_devices[i].fd, > >> + }; > >> + struct kvm_device_attr attr = { > >> + .group = KVM_DEV_VFIO_DEVICE, > >> + .attr = KVM_DEV_VFIO_DEVICE_TDI_BIND, > >> + .addr = (__u64)¶m, > >> + }; > >> + > >> + if (ioctl(kvm_vfio_device, KVM_SET_DEVICE_ATTR, &attr)) { > >> + pr_err("Failed KVM_SET_DEVICE_ATTR for KVM_DEV_VFIO_DEVICE"); > >> + return -ENODEV; > >> + } > >> + > > > > I think bind (which brings device to a LOCKED state, no MMIO, no DMA) > > cannot be a driver agnostic behavior. So I think it should be a VFIO > > ioctl. > > > > For the current CCA implementation bind is equivalent to VDEV_CREATE > which doesn't mark the device LOCKED. Marking the device LOCKED is > driven by the guest as shown in the steps below. Could you elaborate why vdev create & LOCK can't be done at the same time, when guest requests "lock"? Intel TDX also requires firmware calls like tdi_create(alloc metadata) & tdi_bind(do LOCK), but I don't see there is need to break them out in different phases. > > > >> > >> Now in the guest we follow the below steps > >> > >> step 1: > >> echo ${DEVICE} > /sys/bus/pci/devices/${DEVICE}/driver/unbind > >> > >> step 2: Move the device to TDISP LOCK state > >> echo 1 > /sys/bus/pci/devices/0000:00:00.0/tsm/connect > >> echo 3 > /sys/bus/pci/devices/0000:00:00.0/tsm/connect > > > > Reuse the 'connect' interface? I think it conceptually brings chaos. Is > > it better we create a new interface? > > > > I was looking at converting these numbers to strings. > "1" -> connect What does "connect" do in guest? Thanks, Yilun > "2" -> lock > "3" -> run > > > > > >> > >> step 3: Moves the device to TDISP RUN state > >> echo 4 > /sys/bus/pci/devices/0000:00:00.0/tsm/connect > > > > Could you elaborate what '1'/'3'/'4' stand for? > > > > As mentioned above, them move the device to different TDISP state. > > I will reply to this patch with my early RFC chnages for tsm framework. > I am not yet ready to share the CCA backend changes. But I assume having > the tsm framework changes alone can be useful? > > -aneesh
